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821.
延河流域生态环境动态监测系统与应用 总被引:5,自引:1,他引:5
以遥感 (RS)、地理信息系统 (GIS)、全球定位系统 (GPS)为核心技术 ,采用 ETM/ TM卫星数据、航空机载对地观测数据 ,结合地面测试和综合调查方法 ,完成了延河流域面积 10 0 15 .797km2的生态环境本底调查 ,建立了 1990~2 0 0 0年的生态环境动态监测系统。查明了区内主要物种和植被分布 ,土地利用 /土地覆盖现状及其动态变化 ,划分出 5个生态区 ,2 5个生态系统 ,提出了延河流域生态建设. 相似文献
822.
Ma Jun Song Jinming Li Xuegang Yuan Huamao Li Ning Duan Liqin Wang Qidong 《中国海洋湖沼学报》2020,38(4):1215-1224
An investigation was carried out in the Y3 seamount area of the Western Pacific Ocean in December 2014,and the distribution of dissolved inorganic carbon(DIC) and its relationship with environmental factors in this area were explored.The results show that DIC concentration was higher in the adjacent waters of the Y3 seamount area,and the uplift of DIC isolines at the stations was close to the seamount.Meanwhile,interaction between the North Equatorial Current(NEC) and the Y3 seamount affected the DIC distribution i.e.,the upwelling in the same direction of the NEC was obvious,resulting in a decreasing trend of average concentration of DIC in the 200 m water column from the top to the two side s in this direction but in the cross direction.The DIC concentration increased with the water depth increase,and its distribution was affected by various environmental factors.In the surface water,high temperature was a decisive factor for the decrease of the DIC concentration,but the photosynthesis of phytoplankton showing only a weak influence.In the North Pacific Tropic Water(NPTW),DIC production rate from organic matter decomposition was higher than that of DIC consumption by phytoplankton photosynthesis,leading to a continual increase of DIC.In the North Pacific Intermediate Water(NPIW),organic matter decomposition played a leading role in the increase of DIC.In the deep water,decomposition of organic matter weakened,and the dissolution of CaCO_3 controlled the carbonate system,and DIC had the smallest variation range. 相似文献
823.
On the basis of the conductivity temperature depth(CTD)observation data off the coast of the Philippines(7.5°–18°N,130°E–the east coast of the Philippines)in the fall of 2005,the water mass distribution,geostrophic flow field,and heat budget are examined.Four water masses are present:the North Pacific Tropical Surface Water,the North Pacific Sub-surface Water,the North Pacific Intermediate Water,and the Antarctic Intermediate Water(AAIW).The previous three corresponded with the North Equatorial Current(NEC),the Kuroshio Current(KC),and the Mindanao Current(MC),respectively.AAIW is the source of the Mindanao Undercurrent.The mass transport of NEC,KC,and MC is 58.7,15,and 27.95Sv,respectively(relative to 1500db).NEC can be balanced by the transport across the whole transect 18°N(31.81 Sv)and 7.5°N(26.11 Sv)but not simply by KC and MC.Direct calculation is used to study the heat flux.In sum,1.45PW heat is transported outwards the observed region,which is much more than that released from the ocean to the air at the surface(0.05PW).The net heat lost decreased the water temperature by 0.75℃each month on average,and the trend agreed well with the SST change.Vertically,the heat transported by the currents is mainly completed in the upper 500 m. 相似文献
824.
GONG Chuanzhang LI Guangxue LIU Yong DING Dong XU Jishang MA Yanyan QIAO Lulu and WANG Haoyin 《中国海洋大学学报(英文版)》2020,19(1):113-123
Through the geochemical analysis of two hundred-meters cores KD4 and ZK3 from Laizhou Bay,in this study,we determined the distribution law and controlling factors of the geochemical elements.We analyzed 24 elements with respect to their R factors and major principal components,which were combined with the source discrimination functions DFCr/Th and DFCa/Al to obtain the sediment source index and its variation with depth for this area.A comparison of the changes in climate indicators suggests a clear correlation between the source and climate changes.The results show that the Yellow River and surrounding short-term rivers are the main sediment sources in this area.The PC3 of the KD4 core and PC2 of the ZK3 core(e.g.,CaO,MnO,SiO2)exhibit significant variations and reflect the relative contributions of Yellow River sources.The deposition process can be divided into six stages:in Phase I(MIS 5c–MIS 5a),the Yellow River formed,and the composition of the Yellow River had a greater influence on the sedimentary composition of the study area.In Phase II(MIS 5a–MIS 3),the sediment sources of the Yellow River and the short-term streams in this area were wavering,with the sediments derived from short-term rivers playing a more important role.In Phase III(MIS 3),with a sharp drop in temperature,the study area was in the process of retreat,and the sediment source changed from the Yellow River to short-term rivers,after which the Yellow River source material remained the main sediment source for the region.A similar process occurred three more times in Phase IV(MIS 3–MIS 2),Phase V(MIS 2–MIS 1),and Phase VI(MIS 1).With changes in climate,especially during alternating sea-land phases,the sediment source varied in marine-terrestrial-marine phases,and the changes are observed as Yellow River source-surrounding provenance-Yellow River source.However,this process of change is not synchronized with the sea-land strata alternation. 相似文献
825.
【目的】通过化学诱导方法从一株海洋真菌Hypocrea lixii中获得多样化的活性小分子化合物。【方法】对菌株在盐酸普鲁卡因的化学诱导作用下进行固体发酵,代谢产物采用硅胶减压柱层析、Sephadex LH-20以及pHPLC等手段分离纯化,对化合物运用NMR、MS等波谱学技术并比对文献进行结构鉴定,采用Ellman比色法及DPPH自由基清除法对化合物进行初步抗乙酰胆碱酯酶(AChE)和抗氧化活性测试。【结果】从海洋真菌Hypocrea lixii在盐酸普鲁卡因诱导下的发酵提取物中分离得到4个异黄酮类化合物,包括6'-O-crotonylgenistin(1)、Genistein(2)、Daidzein(3)和Genistin(4),以及对氨基苯甲酸甲酯(5)、对羟基苯丙酸(6)和胞嘧啶(7),其中化合物1和6为该种中首次报道,化合物5为生物转化来源首次报道,化合物2~4可能源自培养基。在100μmol/L剂量浓度下,化合物1~4对AChE的抑制以及DPPH自由基的清除活性均较弱,化合物5和6显示了相对强的AChE抑制活性,抑制率分别为40%和38%。【结论】盐酸普鲁卡因对该菌次级代谢产生了显著的影响,为深入研究该菌株化学诱导次级代谢产物提供基础。 相似文献
826.
Based on the sequence data of the nuclear ribosomal DNA internal transcribed spacer (ITS) 1, 5.8 S, and ITS 2, the molecular
phylogeny was analyzed on Ulvaceae species collected from Qingdao coasts in summer of 2007, including 15 attached Ulva and Enteromorpha samples from 10 locations and 10 free-floating Enteromorpha samples from seven locations. The result supported the monophyly of all free-floating Enteromorpha samples, implying the unialgal composition of the free-floating Enteromorpha, and the attached Ulvaceae species from Qingdao coasts were grouped into other five clades, suggesting that they were not
the biogeographic origin of the free-floating Enteromorpha in that season.
Supported by NSFC (40506030); the Innovative Key Project of the Chinese Academy of Sciences (KZCX2-YW-209); Science & Technology
Project of Qingdao City (06-2-2-12-JCH) 相似文献
827.
Dynamics and relationships of Ca, Mg, Fe in litter, soil fauna and soil in Pinus koraiensis-broadleaf mixed forest 总被引:1,自引:0,他引:1
The Liangshui Natural Reserve in Heilongjiang Province of China was selected as the study area. The authors collected the samples of forest litter (Tilia amurensis, Fraxinus mandshurica, Pinus koraiensis, Acer mono, Betula costata, and mixed litter), soil in humus horizon (0--5cm) and soil horizon (5-20cm), and soil macrofauna (Oligochaeta, Geophiloporpha and Juliformia) from 2001 to 2002. The role of soil macrofauna in the material cycle was analyzed through comparing the macro-element contents among various parts of the subsystems and using enrichment index (El). The results indicate that dynamic changes of various litters are very complicated. The contents of Fe in each kind of litter increase firstly, and then decrease in the study period. The changes of macro-element contents are greater in the broad-leaf litter than in the coniferous litter, and the mixed litter is in the middle level, but the differences among them are not significant. The contents of Mg and Fe in humus are higher than those in soil, but the contents of Ca in soil are higher than that in humus. The dynamic changes of macro-element contents in soil and soil fauna are not consistent with those in litter. The diplopod presented obvious enrichment of Ca and Mg (E1〉1), but it does not significantly enrich Fe. Earthworm has a stronger enrichment ability of Fe than diplopod and scolopendra, but E1〈1. Soil fauna can make great influences on the material cycle of the subsystems. 相似文献
828.
该文以山东半岛城市群作为研究对象,构建产业生态化综合评价指标体系,运用熵值法与主成分分析方法,探讨了山东半岛城市群产业生态化总体水平的时空分异特征及影响因素。结果表明:2004—2016年,山东半岛城市群产业生态化呈现上升趋势,山东半岛城市群产业生态化发展水平不断提高;山东半岛城市群产业生态化空间分异现象显著,形成了以济南和青岛为核心的两极化发展特征;山东半岛城市群产业生态化发展水平的区域化现象愈加明显,呈现出NE—SW走向的不均衡发展;山东半岛城市群产业生态化发展影响因素为区域经济发展水平、政府监管水平、外资利用差异以及区域科学技术差异。 相似文献
829.
830.
邢家山大型钼钨矿床位于胶东栖霞-蓬莱-福山金及多金属成矿区东部,矿床主要赋存于晚侏罗世二长花岗岩外接触带的变质地层中,倒转向斜分布区是钼钨成矿有利部位。幸福山岩体为成矿母岩,粉子山群的碳酸盐岩既易交代成矿亦形成了屏蔽层,NW向张扭性断裂导矿,层间裂隙、节理和矿物间隙沉淀成矿。钼钨矿化作用与矽卡岩化、钾化、硅化密切相关,矿床工业类型属矽卡岩型-斑岩型,成因类型属于岩浆期后热液矿床,矿石建造属钨钼建造,该成果对在胶东地区寻找同类型钼矿床具有重要意义。 相似文献